HARRISBURG, Pa. -- When Giants prospect Carson Whisenhunt was playing travel ball in North Carolina, he got to know some of the umpires who were regulars behind the plate. One day, he learned that one of them was named Bumgarner.
"I was like, 'Wait a minute ...' " Whisenhunt told NBC Sports Bay Area recently. "I asked him, 'Is that your son?' "
The umpire was indeed Madison Bumgarner's father, and he and Whisenhunt would end up talking often. When Kevin Bumgarner had a break between games, Whisenhunt often would sit with him and listen to stories about the mindset of one of the best players in the history of a Giants franchise that later would take him in the second round of the 2022 MLB Draft.
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It wouldn't quite be accurate to say that Whisenhunt since has developed into the organization's best left-handed prospect since Bumgarner, because Kyle Harrison took that mantle first. But Whisenhunt, just a year out of college, has moved so quickly that he has joined Harrison on top 100 prospect lists, and as soon as next year, he could join him in a big league rotation.
Whisenhunt has been one of the best stories of the season for the organization, making quick work of Low-A and then High-A. After striking out five over four shutout innings on Saturday, he has a 3.20 ERA in Double-A and 2.45 ERA on the season.
Like Harrison, Whisenhunt was selected to represent the Giants in this year's Futures Game, a showcase for the game's best prospects. In a scoreless relief inning, he showed off the pitch that has him on the fast track. Whisenhunt's changeup is a "plus-plus" pitch per scouts, and he used it to strike out a pair, including Jackson Holiday, widely considered the No. 1 prospect in the minors.
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"You could tell them it's coming and they still can't hit it. It's a very effective pitch," Richmond Flying Squirrels manager Dennis Pelfrey said. "As long as he continues to throw the fastball for strikes, he's going to do a lot of really good things with the changeup and give himself a chance to get guys out every single time."
The dominant changeup is the result of years of tinkering, and it's actually not just one pitch. Whisenhunt didn't throw any breaking balls until he got to high school, so the changeup became his out pitch at a young age. He messed with the grip, arm angle and pressure points at times, but it didn't take long for him to figure out that he might have something special. As a sophomore in high school, Whisenhunt realized it was separating him from others.
The 22-year-old now throws three variations of his changeup and he commands all of them. Depending on the situation, he'll mix and match during games.
"If I'm behind in the count and don't want to throw a middle-middle heater, I have one that doesn't move as much that I can steal a strike with," he said. "And depending on the barrel path and their swing, I have two -- one that fades out with more movement and then one that's straight down. It just depends on the hitter and what me and the catcher are seeing at the same time."
Being left-handed and throwing that kind of changeup alone would make Whisenhunt a good prospect, but he pairs it with a good fastball that was 96 mph in the Futures Game and sits in the low-to-mid 90s most nights. He also mixes in a curveball, which is getting more play in Double-A as Giants coaches try to build out his repertoire.
Whisenhunt has 83 strikeouts in 58 2/3 innings this year and has held opposing hitters to a .177 average and just three homers. The changeup has done most of that damage, but he knows he needs more as he continues to climb.
"The changeup has always been there, so now me and our pitching coaches here have been talking about trying to set it up," he said. "They want me to use the curveball more and then obviously work on the fastball command, which is definitely getting better. Having that third pitch is going to be big, but obviously the changeup is still going to be my go-to. It doesn't matter if you're a lefty or righty."
The early success this year has Whisenhunt up to No. 90 on Baseball America's current top 100 and No. 95 on MLB Pipeline's list, validating every feeling the Giants had about him before the draft. The Giants considered him with their first-round pick last year, but when left-hander/DH Reggie Crawford dropped because of Tommy John surgery, they scooped him up.
A PED suspension at East Carolina cost Whisenhunt the 2022 college season, but the Giants were happy with their reports on his makeup and thrilled when he dropped to the 66th pick in last year's draft. Whisenhunt recalls draft night as being "very hectic" because of the uncertainty, and this year has nearly matched that.
After just four starts in San Jose, Whisenhunt was bumped up to Eugene, where he allowed just nine hits over 25 1/3 innings. The promotion to Double-A came after six starts in High-A, and the Giants are working to manage Whisenhunt's Double-A workload since he didn't pitch much in 2022.
In part because of the trip to Seattle for the Futures Game, he has thrown just nine innings in July, but if the results -- five hits, six walks, 12 strikeouts -- are any indication, it might not be long before he's back in California, making a cameo in Triple-A that could set up a 2024 big league debut.
"It's definitely happened faster than I thought it would, but the biggest thing is just trying to keep the same mentality every time I go out there," he said. "I didn't expect to move this quickly since I got here, but I've enjoyed every step of it so far."